While I won't advise against trying out stuff in general, it won't help you much when selecting speakers. This sounds counter-intuitive, but the problem here is that you will be listening to speakers in a room, which isn't your room. But the room determines a lot of what you hear below ~300 Hz and the balance between bass and treble is very important to judge, whether you like a particular pair of speakers or not.
If you're very lucky and find a dealer with a listening room that is similar in size and setup (tables, window positions and sizes, amount of carpet and so on), it might still be useful to go there to compare. In most other cases, it may be better to look at the measurements of the 707 S2, see what you would like to change about them and then look for measurements of other speakers to see if they fit your target.